Abstract: A plurality of pump light sources generate plural variations of pump light having different frequencies. A modulation circuit intensity-modulates the plural variations of pump light in the predetermined periods, respectively. A pump light pair whose frequency difference equals a Raman shift frequency are modulated such that they cannot simultaneously enters an emission state. A wavelength-multiplexer wavelength-multiplexes the plural variations of pump light modulated by the modulation circuit. A optical guide device guides the plural variations of pump light wavelength-multiplexed by the wavelength-multiplexer to an optical fiber.

Abstract: A liquid crystal display device includes a liquid crystal display panel and a metal shield casing which covers a periphery of the liquid crystal display panel. The metal shield casing has a plurality of fixing pawls and a plurality of fixing hooks.

Abstract: A vacuum cleaner includes an electric blower for generating a suction air stream and a dust collecting unit for collecting dirt particles contained in the suction air stream. The suction air stream passing through the dust collecting unit into the electric blower flows in an approximately linear path. A dust removing unit is provided for removing dirt particles adhered to the dust collecting unit. The dust removing unit is preferably disposed adjacent to a communication hole between the dust collecting chamber and an electric blower chamber.

Abstract: The present invention has an object to provide a technology for monitoring the quality of a WDM signal light, capable of quickly and accurately judging an occurrence of quality deterioration of signal light and a deterioration factor thereof. To this end, according to a quality monitoring apparatus of WDM signal light of the present invention, a part of the WDM signal light being propagated through an optical transmission path is branched as a monitor light, a signal light of one wavelength contained in the monitor light is selected as a channel to be measured.

Abstract: An optical sending apparatus of this invention includes a plurality of optical signal generating sections, a dispersion compensating section and a wavelength multiplexing section. The dispersion compensating section performs compensation with a predetermined chromatic dispersion value to at least one of polarized light generated by the optical signal generating sections while a predetermined state of polarized light is maintained. The wavelength multiplexing section combines output light outputted from the optical signal generating section with output light passing through the dispersion compensating section so that the polarized light of adjacent wavelengths crosses orthogonal to each other. The optical sending apparatus having such a construction can generate high-density WDM optical signals, the dispersion of which is compensated in advance, by a polarization crossing method.

Abstract: The present invention has an object to provide an optical transmission technology using Raman amplification wherein a supervisory signal transferred among a plurality of optical transmission apparatuses is superimposed on a main signal light by using a pumping light for Raman amplification. To this end, a Raman amplifier applied with the optical transmission method of the present invention, is provided with a supervisory signal superimposing section for superimposing a supervisory signal transferred among the optical transmission apparatuses on at least one of a plurality of pumping lights of different wavelengths to be supplied to a Raman amplification medium via a multiplexer from a pumping light generating section, thereby transmitting the main signal light propagated through the Raman amplification medium to be Raman amplified, which is superimposed with the supervisory signal.

Abstract: A liquid crystal display device includes a liquid crystal display panel and a metal shield casing which covers a periphery of the liquid crystal display panel. The metal shield casing has a plurality of fixing pawls and a plurality of fixing hooks.

Abstract: A liquid crystal display device including a liquid crystal display panel, a first driver circuit substrate, a second driver unit substrate and a flexible connector. The first driver circuit substrate provides electrical connection for at least one driver chip for the liquid crystal display panel with the first driver circuit being disposed at a peripheral portion of the liquid crystal display panel. The second driver circuit substrate has at least a connector to be connected with an external circuit with the second driver circuit substrate being disposed in superposed relation to at least a portion of the first driver circuit substrate. The flexible connector electrically connects at least a part of the first driver circuit substrate to at least a part of the second driver substrate.

Abstract: The present invention aims at providing an optical transmitter utilizing a Mach-Zehnder type optical modulator, in which the optical modulator is capable of readily optimizing an optical wavelength chirp to be added to a transmission optical signal. To this end, the optical transmitter of the present invention includes a Mach-Zehnder type optical modulator having two arms driven by two drive signals, respectively, and is constituted to comprise: amplitude adjusting parts for adjusting the amplitudes of the drive signals, respectively; phase adjusting parts for adjusting the phases of the drive signals, respectively; an amplitude controlling part for feedback controlling the amplitude adjusting parts so that an amplitude ratio between the drive signals becomes a value corresponding to an optimum optical wavelength chirp amount; and a phase controlling part for feedback controlling the phase adjusting parts so that the phases of the drive signals are brought into an antiphase relation.

Abstract: A virtual store server is provided in a virtual store of at least one of tie-up companies. The virtual store is established on the internet so as to issue points to a member upon access to the virtual store. The virtual store server includes a virtual store point DB for recording the number of the issued points. When the member makes a purchase in the actual store with the number of points that has been read by at least one terminal provided in an actual store, the terminal functions in reducing the number of points that has been read and used in the actual store.

Abstract: An optical modulator having a voltage-optical output characteristic in which optical output varies periodically with respect to a voltage value of an electrical drive signal is driven by a modulator driving voltage signal, which has an amplitude of 2·V&pgr; between two light-emission culminations or two light extinction culminations of the voltage-optical output characteristic. A low-frequency superimposing unit superimposes a prescribed low-frequency signal on the modulator driving voltage signal, and an operating-point controller controls the operating point of the optical modulator by detecting operating-point drift of the optical modulator based upon the low-frequency signal component contained in an optical signal output from the optical modulator and controlling the bias voltage of the optical modulator in dependence upon the drift of the operating point of the optical modulator.

Abstract: The present invention aims at providing an optical transmitter utilizing a Mach-Zehnder type optical modulator, in which the optical modulator is capable of readily optimizing an optical wavelength chirp to be added to a transmission optical signal. To this end, the optical transmitter of the present invention includes a Mach-Zehnder type optical modulator having two arms driven by two drive signals, respectively, and is constituted to comprise: amplitude adjusting parts for adjusting the amplitudes of the drive signals, respectively; phase adjusting parts for adjusting the phases of the drive signals, respectively; an amplitude controlling part for feedback controlling the amplitude adjusting parts so that an amplitude ratio between the drive signals becomes a value corresponding to an optimum optical wavelength chirp amount; and a phase controlling part for feedback controlling the phase adjusting parts so that the phases of the drive signals are brought into an antiphase relation.

Abstract: The present invention relates to an optical transmitter and particularly to an optical transmitter including an external optical modulator such as Mach-Zehnder type optical modulator which modulates the light from a light source to output an optical signal with a drive voltage signal generated depending on an input signal According to the present invention is achieved by providing an optical modulator, which add weighting to operating point control signal in accordance with optical output level of the modulator.

Abstract: An optical modulator having a voltage—optical output characteristic in which optical output varies periodically with respect to a voltage value of an electrical drive signal is driven by a modulator driving voltage signal, which has an amplitude of 2·V&pgr; between two light-emission culminations or two light extinction culminations of the voltage—optical output characteristic. A low-frequency superimposing unit superimposes a prescribed low-frequency signal on the modulator driving voltage signal, and an operating-point controller controls the operating point of the optical modulator by detecting operating-point drift of the optical modulator based upon the low-frequency signal component contained in an optical signal output from the optical modulator and controlling the bias voltage of the optical modulator in dependence upon the drift of the operating point of the optical modulator.

Abstract: A liquid crystal display device including a liquid crystal display panel, a first driver circuit substrate, a second driver unit substrate and a flexible connector. The first driver circuit substrate provides electrical connection for at least one driver chip for the liquid crystal display panel with the first driver circuit being disposed at a peripheral portion of the liquid crystal display panel. The second driver circuit substrate has at least a connector to be connected with an external circuit with the second driver circuit substrate being disposed in superposed relation to at least a portion of the first driver circuit substrate. The flexible connector electrically connects at least a part of the first driver circuit substrate to at least a part of the second driver substrate.

Abstract: An object is to provide an optical transmission apparatus, an optical repetition apparatus and an optical transmission method in which the chirp polarity applied to an output signal light can be modified easily in accordance with the wavelength dispersion characteristics of a transmission path. Therefore, for example, with the optical transmission apparatus according to the invention a signal light of optical frequency fsig generated by a signal light generating device, and a probe light of optical frequency fp generated by a probe light generation device are input to a four wave mixing generation device having a nonlinear optical effect to generate various signal lights with optical frequencies of fsig, fp, 2×fsig−fp and 2×fp−fsig. One of the signal lights output from the four wave mixing generation device is selected by a signal light selection device and output to the transmission path.

Abstract: An optical modulator having a voltage—optical output characteristic in which optical output varies periodically with respect to a voltage value of an electrical drive signal is driven by a modulator driving voltage signal, which has an amplitude of 2·V&pgr; between two light-emission culminations or two light extinction culminations of the voltage—optical output characteristic. A low-frequency superimposing unit superimposes a prescribed low-frequency signal on the modulator driving voltage signal, and an operating-point controller controls the operating point of the optical modulator by detecting operating-point drift of the optical modulator based upon the low-frequency signal component contained in an optical signal output from the optical modulator and controlling the bias voltage of the optical modulator in dependence upon the drift of the operating point of the optical modulator.

Abstract: A liquid crystal display device including a liquid crystal display panel, a first driver circuit substrate, a second driver unit substrate and a flexible connector. The first driver circuit substrate provides electrical connection for at least one driver chip for the liquid crystal display panel with the first driver circuit being disposed at a peripheral portion of the liquid crystal display panel. The second driver circuit substrate has at least a connector to be connected with an external circuit with the second driver circuit substrate being disposed in superposed relation to at least a portion of the first driver circuit substrate. The flexible connector electrically connects at least a part of the first driver circuit substrate to at least a part of the second driver substrate.

Abstract: A door opening and closing mechanism, wherein a swinging door to cover an opening for loading, unloading, or exchanging discs comprises two doors, an upper door (14) and a lower door (13), each of which is supported by pivots (14a) and (13a). The opening is covered, when closing the doors, with the two doors, the upper door (14) and the lower door (13), by an interlocking motion by engaging a sliding guide (14b) provided on the upper door (14) and a sliding pin (13b) provided on the lower door (13). When opening the doors, the lower door (13) is nested inside the upper door (14) guided by pivots (14a), (13a), the sliding guide (14b), and the sliding pin (13b), whereby the amount of the projection of the doors when open corresponds to the projection only of the upper door (14).

Abstract: A liquid crystal display device which comprises: a shield casing made of a metal plate and having fixing pawls and fixing hooks; an middle frame for holding a liquid crystal display; and a lower casing for packaging back lights, wherein the fixing pawls of said shield casing are bent in corresponding recesses formed in the middle frame, and wherein the fixing hooks of said shield casing are fitted on corresponding projections formed on the lower casing.